1. Field of the Invention
The present invention relates to a trackball, as an input device, for a portable computer such as a notebook computer, a laptop computer, etc. More particularly the present invention relates to a trackball for a portable computer which can be operated not only when the trackball is mounted on a main body of the portable computer but also when it is detached from the main body of the portable computer.
2. Description of the Prior Art
In a computer, an input device thereof for entering data by moving a cursor on a display is generally either a mouse being operated in an area separate from the main body of the computer, or a trackball being manipulated while it mounted on the main body of the computer. A cursor on the display of the computer is moved by operation of a mouse which works in an area separate from the main body of the computer. The cursor is also moved by manipulation of a trackball which works while mounted on the main body of the computer.
In such a conventional trackball-mounted portable computer, as shown in FIG. 1, a display assembly 200 for displaying alphanumeric information and data, a keyboard assembly 201 for entering data, a top cover 202 for supporting the keyboard assembly 201 as a top-side enclosure of the computer, a bottom cover 203 for being assembled with the top cover 202, and a trackball 204 installed on the top cover 202 for making a cursor on the display assembly 200 move are provided.
In operation, if a user rotates a ball on the trackball 204, a cursor on the display moves so that an appropriate menu can be chosen.
However, in such a conventional trackball-mounted portable computer, since the trackball is fixed at the main body of the portable computer, it is inconvenient to use the trackball in a separate place from the portable computer. Even though a wired mouse can be used, since the length of the wire is restricted, the working space is to be limited.